The Mechanics of Earthquakes and Faulting

Transcription

1 The Mechanics of Earthquakes and Faulting Christopher H. Scholz Lamont-Doherty Geological Observatory and Department of Earth and Environmental Sciences, Columbia University 2nd edition CAMBRIDGE UNIVERSITY PRESS

2 Preface to the first edition xi Preface to the second edition xv Acknowledgments xvii List of symbols xx 1 Brittle fracture of rock 1.1 Theoretical concepts Historical Griffith theory Fracture mechanics Crack models Macroscopic fracture criteria Experimental studies of rock strength Macroscopic strength Fracture energies Discussion of fracture criteria in the light of experimental results Effect of scale on strength Pore fluid effects on fracture Laws of effective stress Environmental effects on strength The brittle-plastic transition General principles The transition induced by pressure The transition induced by temperature Extrapolation to geological conditions 50 2 Rock friction 2.1 Theoretical concepts Historical The adhesion theory of friction Elastic contact theory of friction Otherfrictional interactions 63 Vll

3 viii Contents 2.2 Experimental observations of friction General observations Effects of other variables on friction Wear Stick slip and stable sliding Introduction Rate effects on friction: the rate and state variable friction laws Frictional stability regimes Dynamics of stick slip Friction under geological conditions 97 Mechanics of faulting 3.1 Mechanical framework Anderson's theory of faulting Hubbert-Rubey theory of overthrust faulting Stress in the crust, fault reactivation, and friction The formation and growth of faults The problem of fault formation Growth and development ef faults Fault interactions and fault populations Fault rocks and structures Fault rocks and deformation mechanisms Fabrics and surfaces Strength and rheology of faults A synoptic shear zone model Deep ductile shear zones: the downward continuation of faults Thermomechanical effects of faulting The debate on the strength of crustal fault zones Fault morphology and mechanical effects of heterogeneity Fault topography and morphology Mechanical effects of fault irregularities 173 Mechanics of earthquakes 4.1 Historical development Theoretical background The dynamic energy balance Dynamic shear crack propagation Simple applications to earthquake rupture Earthquake phenomenology Quantification of earthquakes Earthquake scaling relations Observations of earthquakes Case studies Earthquake sequences Compound earthquakes: Clustering and migration 229

4 ix 4.5 Mechanics of earthquake interactions Coulomb stress loading Mechanisms for the time delay 237 The seismic cycle 5.1 Historical The crustal deformation cycle Geodetic observations of strain accumulation Models of strain accumulation Postseismic phenomena The earthquake cycle Earthquake recurrence Geological observations of recurrence times Recurrence estimation with insufficient data Seismicity changes during the loading cycle The question of earthquake periodicity Earthquake recurrence models 294 Seismotectonics 6.1 Introduction Seismotectonic analysis Qualitative analysis Quantitative analysis Comparative seismotectonics Subduction zone seismicity Oceanic earthquakes Continental extensional regimes Intraplate earthquakes Mechanism of deep earthquakes Slow and tsunamigenic earthquakes The relative role of seismic and aseismic faulting Aseismic slip Seismic coupling of subduction zones Induced seismicity Some examples Mechanisms of reservoir-induced seismicity Mining-induced seismicity Induced seismicity as a stress gauge 350 Earthquake prediction and hazard analysis 7.1 Introduction Historical Types of earthquake prediction Is earthquake prediction possible? 356

5 7.2 Precursory phenomena Preinstrumental observations Intermediate-term precursors Short-term precursors Mechanisms of precursory phenomena Nucleation models Dilatancymodels Lithospheric loading models Critical point theory Comparison of models and observations Earthquake prediction experiments Earthquake hazard analysis Traditional methods Long-term hazard analysis Analysis of instantaneous hazard Future prospects and problems 412 References 415 Index 467 The plate section is between pp